Sinner is currently serving a three-month suspension after he failed doping tests in March 2024, with the timing of his ban raising some eyebrows as he will not miss any Grand Slam events and will be back in time to play in his home Masters event in Rome next month.
Several top players have privately expressed their support for Sinner after what most observers believe was a mistake from his team that contributed to his urine sample delivering a positive result.
Yet none have been as outspoken as Draper in his support of the Italian, as he gave his views to the BBC and the Guardian.
"When people ask about Jannik I tell the truth - I think he is a really genuine, nice person and on top of that he is an unbelievable player," said Draper.
"In this situation, I am sure he would have had absolutely zero idea of anything. That's the way life goes - sometimes there are mistakes.
"In terms of how I feel about him as a person I think it is important for people to know and recognise the guy is kind-hearted and a good human being. He doesn't deserve any of the hate he gets."
That are comments that highlight Draper's unequivocal support for Sinner and he highlights the bond he has with the player who beat him in last year's US Open semi-finals by practising with him in Monte Carlo last week and he counts down to his return to the ATP Tour.
"I knew Jannik was available and in Monte Carlo on the clay so we organised with his team to go out there for three or four days and train with him," Draper said.
"If you're going to train with anyone, it has got to be the best in the world, right?
"He's obviously had a bit of time off, but he's playing at an incredible level still.
"It was great to be around him for a few days and get some good sparring. I'm looking forward to having him back on the tour because I think his presence has been missed."
The comments from world No. 6 Draper may raise a few eyebrows, as the brutal reality will always be that Sinner tested positive for a banned anabolic steroid.
Former Wimbledon finalist Nick Kyrgios has been Sinner's most outspoken critic, as he has questioned the explanation given for the doping violation.
Yet it is clear that Sinner has high-profile support among his rivals, with Draper relishing the chance to take on a player he aspires to challenge for the biggest titles in tennis over the next decade.